Juan Carlos S. answered 04/09/19
3D Modeling Instructor
There are only a few movies made in real 3D, the one that I remember right now is "Avatar" (one of my favorite movies) from James Cameron, I am sure there just a few more. Capturing movies natively in 3D is much expensive and take a lot more time and effort to create than regular movies. The movies that you see in 3D/stereoscopic are captured as regular 2D movies and then converted to 3D/stereoscopic creating the illusion of depth in an image. A lot of artists will work frame by frame to separating the background and foreground images to create different levels of depth. Next time you watch a 3D movie take a look in the credits to the amount of stereoscopic artist that worked on it. The biggest name for 3D conversion is "Stereo-D" you can check their website to find out how many movies you thought they were really 3D but were actually converted. I hope this help.